Retroviruses and viral vectors

I have two questions which I hope somebody can help me answer.
1. Is there anyway to remove the reverse transcriptase from a retrovirus
while maintaining the viability of the virus? By this I mean, without
destroying the virus.
2. How are viral vectors created? If I have a piece of DNA (or RNA in
the case of retroviruses) what is standard procedure for getting it into
the viral genome?
Thank you for any help you can offer.
Matthew Dubeck
RRRP87C at prodigy.com